Fuel pump



Jan. 27, 19.70 c PHILLlPs E'TAL 3,491,700

FUEL,' PUMP Filed March 21, 1967 INVENTOR CLAUDE F. PH/LL/PS RUSSELL PARRE/VT ATTORNEY United States Patent O 3,491,700 FUEL PUMP Claude F. Phillips and Russell Parrent, Fairfield, 11]., assignors to Airtex Products, Division of United Industrial Syndicate, New York, N.Y., a corporation of New York Filed Mar. 21, 1967, Ser. No. 624,866 Int. Cl. F04b 43/02 US. Cl. 103-150 1 Claim ABSTRACT OF THE DISCLOSURE FIELD OF THE INVENTION The invention resides in the field of fuel pumps for automotive vehicles.

DESCRIPTION OF PRIOR ART The prior art uses sheet metal components as body elements in fuel pumps. However, various practical difiiculties resides in such constructions due to leakage particularly where an inner plate is used to separate the valve chambers from the pumping chamber.

SUMMARY OF THE INVENTION The invention comprises cast body members having opposed radial flanges and secured therebetween an internal plate which carries one of the valves and which is peripherally sealed by having a radial face flange fitted into a recess in one of the body member flanges so that its thickness is substantially flush with the radial end face of that flange. The sealing elfect is produced by clamping the peripheral margin of the pumping diaphragm onto the flush surfaces. The other body member flange serves to compress the diaphragm against the flush surfaces. A steel band of sheet metal is crimped around the body members at the juncture of the flange thereof to securely and sealingly hold the assembly. Further, the plate is also sealed at a valve well in the one body member.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 of the drawing shows a cross section in elevation of a fuel pump utilizing the invention; and

FIG. 2 is a view looking in the direction of the arrows 22 of FIG. 1.

DESCRIPTION OF THE INVENTION Referring to the drawing the fuel pump illustrated comprises a pair of body castings and 15, referred to as upper and lower castings hereinafter; however, it will be understood that the pump may be operated in inverted position and, accordingly, the terms upper and lower are merely for purpose of present discussion. The upper casting has the conventional rocker arm arrangement 18 with return spring 22 for actuating diaphragh 25 conventionally clamped between plates as shown, actuation being via the stem 28 in the usual manner.

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Intermediate the castings is a diecast or sheet metal stamped valve and chamber separator plate 32 having a peripheral radial flange 35 which has a face generally flush with the radial end face 38 of flange 39 of the lower casting being disposed in a surrounding annular recess in that flange. Plate 32 holds one of the valves as later explained and separates the fuel chamber F from the pump inlet and outlet connections so that flow takes place through the valves in a conventional manner. The margin of diaphragm 25 is disposed on and across the juncture of the flush surfaces and is securely compressed thereagainst by the upper casting flange 40, the radial end surface of which is formed with a slight ridge 42 so as to very fully compress the diaphragm and strongly grip and seal the same. A groove 43 in the end face of flange 40 is also provided into which said diaphragm expands to further effect sealing. The two body castings are securely and compressively held together by a sheet metal band 45 crimped around the adjacent end flanges in a manner heretofore known.

The above construction utilizing only the fuel pump diaphragm as a seal for both the inner plate and the castings junctures has been found to be very practical from the standpoint of precluding leakage and, of course, the construction eliminates the large plurality of bolts and threaded holes generally found in numerous prior art constructions.

The plate 32 carries an outlet valve 48 suitably secured therein by a sealing force fit within a skirted aperture 51. The outlet construction of valve well and port 54 is conventional, being part of the lower casting.

The pump inlet construction 57, conventionally cast as part of the lower casting, leads to the valve well 60 in which is force fitted an inlet valve 63 aligned with an aperture 66 in plate 32. The aperture rim is formed axially outwardly in a skirt to be encompassed by a sealing ring 70 and which is compressed in an annular holding recess of the lower casting as shown at the time the plate is gripped in the assembly.

The construction just described has a considerable assembly advantage over known prior art constructions wherein both valves are carried by the inner pla e. In such constructions there is generally a need to make one valve well considerably deeper than the other and this introduces problems in aligning such valve well, formed of the material of the. inner plate, with the casting portion of the well for inlet or outlet, as the case may be. Even then, sealing is required and it is more difficult to accomplish than the arrangement wherein one valve is secured in a body casting aligned with the aperture of the inner plate which is more readily sealed in the casting as to that particular valve by a simple sealing ring 70.

What is claimed is:

1; A fuel pump having a housing comprising a pair of body members and a pumping diaphragm intermediate and separating said body members; a valve plate intermediate said pumping diaphragm and one of said body members and dividing said one body member into a pair of chambers wherein one of said chambers is a fuel chamber; said valve plate having a pair of generally coplanar apertures; a pair of valve units disposed for fllow control to and from said fuel chamber; one valve unit being carried in one aperture of said valve plate and the other valve unit being carried in said one body member generally coaxial with the other aperture in said valve plate and disposed in the other chamber; and means for sealing said valve plate to said one body member circumferentially around said other aperture and around said 3,291,064 12/1966 Foster 103-150 other valve unit, whereby to isolate said chamber. 3,304,880 2/ 1967 Gold et a1 103-150 3,330,216 7/1967 Schmmelpfenig 103-150 References t d 3,364,869 1/1968 Toschkoff 103 150 UNITED STATES PATENTS 5 3,335,641 8/1967 Toschkoff 103150 2,469,818 5/1949 Erickson 1O3 150 3,364,870 1/1968 Quatredenlers et a1. 103150 2,7 86,423 3/ 1957 C fi 103 150 WILLIAM L. FREEH, Primary Examiner 2,901,977 9/1959 Snyder 10315O 

